A toroidal continuously variable transmission for a vehicle continuously varies a speed ratio according to a variation of a gyration angle of power rollers gripped by an input disk and an output disk. Tokkai Hei 7-198015 published by the Japanese Patent Office in 1995 discloses an oil pressure mechanism for varying the gyration angle of the power rollers. The oil pressure mechanism comprises a spool type oil pressure control valve driven by a step motor, and a feedback mechanism which feeds back the gyration angle of one of the power rollers to the oil pressure control valve via a precess cam and an L-shaped link.
When the oil pressure control valve is operated via the step motor, an oil pressure supplied to the continuously variable transmission from the oil pressure control valve varies, and the gyration angle of the power roller varies. This variation is fed back to the oil pressure control valve via the feedback mechanism, and the gyration angle of the power roller is controlled to a target gyration angle by stopping rotation of the step motor when the real gyration angle of the power roller coincides with the target gyration angle.
One end of the L-shaped link of the feedback mechanism is in contact with the precess cam, and the other end is connected to a rod joined to the spool of the oil pressure valve so that the displacement of the precess cam in the axial direction and rotation direction is transmitted to the spool.
The spool is pushed towards the L-shaped link by a spring housed in the oil pressure control valve so as to maintain this contact state.